* Update go-containerregistry
Update go-containerregistry since it can now handle image names of the
format repo:tag@digest.
Should fix#535.
Thanks @ViceIce for the fix!
* update go-containerregistry again
* dep ensure and use k8schain
* checkpoint
* fix vendoring, stuff builds
* Use k8schain for pushes too
* Use NewNoClient
* update ggcr dep
* Move k8schain usage to image_util.go